Targeted behavioral advertising is where a user’s online activity is tracked so that ads can be served based on the user’s behavior. What began as online data gathering has expanding — now there’e the online and offline data collection and tracking of the habits of consumers. There have been numerous news stories about this privacy and surveillance issue. There is a fundamental issue about targeted behavioral advertising that divides industry and consumer advocates: opt-in or opt-out. Opt-in, the choice of consumer advocates, puts the burden on companies to have strong privacy protections and use limitations so consumers will choose to share their data. Opt-out, the choice of the majority of ad industry players, puts the burden on consumers to learn about what the privacy policies are, whether they protect consumer data, whom the data is shared with and for what purpose, and how to opt-out of this data collection, use and sharing.

Companies can also buy information on individuals from data collectors. At times, the information can be wrong, causing problems for individuals. Read a previous post for more about data brokers.

What happens when data is gathered as a person browses the Internet? It can lead to innocuous advertisements for cars when you’re searching for a new vehicle or boots when you’re considering replacing ones that wore out last winter. Or it can lead to a more difficult situation when you’re faced with ads strollers and car seats showing up on Web sites that you visit even though you had a miscarriage a month ago. It’s easy for advertisers to connect the dots when someone starts searching for infant safety gear or reading parenting Web sites and the person is unable to opt-out of targeted behavioral advertising.

The fact that such personal medical information can be discovered by companies can cause individuals to go to extremes in protecting their privacy. For example, last year, Forbeswrote about a woman who “treated her impending birth as many people might treat online criminal activity. She paid for maternity clothes in cash, insisted friends and families not discuss the bump on Facebook, surfed baby sites only with the Tor browser (which masks a user’s IP address), and used a code language to talk about the baby with her husband via text message.” Janet Vertesi told Forbes that she didn’t want companies to know about her pregnancy. “I didn’t want Facebook to know about the pregnancy, and they could do that by data-mining my private messages,” she said. “I certainly had that years ago, when Google knew I was engaged before my family and friends did, based on my chats.” Facebook told Forbes that it does not create targeted advertisements based on private messages.

Vertesi has the financial ability and the tech knowledge to attempt to avoid the tracking and targeting. But what about all of the people who don’t? And why should someone have to go to such extremes to protect his or her privacy?

“Opting out makes you look like a criminal,” Vertesi told Forbes. “People have reasons for privacy that are not terrible ones. They just don’t want everything about them captured by a company and kept.”

As more data is gathered, more people may feel uncomfortable with the tracking and the targeting and attempt to opt-out. People have joined the Do Not Track movement — this can take the form of opting out of being tracked by e-mail address or by having your Web browser send an opt-out signal to a company as you conduct your online activity. There has been difficulty, because some companies choose not to respect Do Not Track signals sent by Web browsers. People also have installed ad-blocker technology to avoid seeing ads.